Rear bumper



FIG. 1 is a top, front and right side perspective view of a rear bumper showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a right side view thereof;

FIG. 7 is a left side view thereof; and,

FIG. 8 is another top, front and right side perspective view thereof shown in use on a vehicle.

The broken lines shown throughout the drawing views are shown form illustrative and environmental purposes and form no part of the claimed design. 

CLAIM The ornamental design for a rear bumper, as shown and described. 